Ratchet-drill.



No. 7|2,856. Patented Nn'v. 4, i902.

0. A. SCHULTZ.

BATGHETDRILL.

(Application led Jan. 2, 1902.)

(No Model.)

#iff/(fet. A.

W/TNESSES v l /N VENT? (y g/azz;

. mamy' THE Nanms PETERS co.. Pnoramrim., wAsHiMnToN. bl'c.,

' UNITED STATES PATENT OFFICE.

.OSKAR ALBERT SCHULTZ, OF ELLERBECK, GERMANY.

RATCHETiDRILL.

SFECIFICATION forming part of Letters VPatent N o. 712,856, ldated.November 4, 1902. Application filed January 2, 190-2. Serial'No. 88,143.(No model) To all whom it may concern.-

Be it known that I, OSKAR ALBERT SCHULTZ, a subject of the Emperor ofGrer-v such as will enable others skilled in the artY to which itappertains to make and use the same, reference being had to theaccompanying drawings, and to letters of reference marked thereon, whichform part of this specification.

The present invention has reference to improvements in ratchet-drills,and relates more especially to an adjustable feed spindle or shaft forratchetdrills; and the object of the invention is to provide afeed-spindle which can be lengthened so as to accommodate thedrilling-tool to the Varying distances from the counter-rest to thevWork-piece without the use of interposed loose parts, as pieces o'fwood or metal, as are used now in places where the boring depth or thedistance from the counter-rest to the Work-piece is comparativelygreat-for instance, in boilers and the like.

According to the present invention the feedspindle is composed ofseveral parts or sections telescoping into one another, which accordingto necessity are drawn out one by one and rigidly secured in thedrawn-out position.

In order to make the invention more readily understood, I haveillustrated it on the accompanying sheet of drawings, in Which- Figure 1represents a longitudinal section through a feed-spindle composed ofthree telescoping sections. Fig. 2 is a side View of the device turnedat an angle of ninety degrees with respect to Fig. 1. Fig. 3 is acrosssection on line d b of Fig. 1, and Fig. Llshows the mode ofconnection with a ratchet-drill.

In the drawings only three telescopingsections are shown, but it isevident that four or more such sections may be provided. The section Breceives the solid extension-piece C. The section A is .provided withthe center point D. Upon the outer surface of the section A are securedtwo or more leaf-springs O, with enlarged upper ends G in the form ofWedges and having inclined or beveled outer faces with noses L, adaptedto project into and through corresponding slots H, provided in the wall,as is clearly shown in the upper part of Fig. 1. The upper end of thesection B is provided with an exterior thread M, upon which threads anut E, havingacone-shaped annular extension N, the inner surface ofwhich has the same degree of slant as the enlarged leaf-spring ends.Upon the nut E being screwed down the noses L are pressed through theslots H and into corresponding recesses H', provided in the solidextension- ,piece C, thereby rigidly securing the latter within thesection B. The saine arrangement of springs, recesses, slots, andconenuts is found with reference to sections A and B and the othersections, however many of them may be used.

The extension-piece C carries a socket-piece J with internal thread forreceiving the intermediate member K, which in turn surrounds thefeed-screw L. The slots H H' may be provided at varying distances orequal distances and may-be marked so that the Workman is enabled todirectly read offthe depth of the bore-hole.

In the operation of the invention the drill may be adapted to bore holesin boilers of different sizes or in other situations Where the bearingof the center point D is too far from Athe point of operation of thedrill-point by connecting up one or more telescoping sections in themanner described, adjustments in shorter distances than whole sectionsbeing made by adjusting the noses L of springs O in different slots H Hof one or more of the inner sections.

The described extension shaft or spindle can easily be fitted to theordinary ratchetdrill by providing the ordinary center-point spindlewith an exterior thread adapted to engage the corresponding interiorthread of the headpiece or socket J.

Having thus fully described my invention, what l claim as n'ew, anddesire to secure by Letters Patent of the United States, is-

An extensible feed shaft or spindle for ratchet-drills, comprising aplurality of telescoping sections, provided respectively with slots andcorresponding recesses, the upper section adapted to receive thefeed-screw and the lower one carrying the center point, leafspringssecured upon the slotted section and having enlarged upper ends andnoses adapted to pass through the slots in one section and engage in therecesses in the other seotion, and a nut with a. cone-shaped annularextension threaded upon the upper end of the slotted section and adaptedto aetuate and hold the upper ends of the said leaf-springs in I theslots and recesses, substantially as and for the purposes speoied.

In witness whereof I have hereunto set my hand in presence of twowitnesses.

OSKAR ALBERT SCHULTZ. Witnesses:

J ULIUs RPKE, WILHELM REDDIEN.

